SEOUL, South Korea — Two South Korean fighter jets collided in midair during a training exercise Tuesday, causing one to crash and dislodging four missiles, the air force said. The missiles did not explode.

The pilot of the crashed jet ejected safely before it went down in a rice paddy in Pocheon, about 30 miles north of Seoul, the air force said in a statement. The other jet returned safely to base, although it was not clear how much damage it sustained in the collision.

Four air-to-air missiles that were loaded on the two F-5E jets dropped to the ground as a result of the collision but did not explode. Three were recovered and troops searched the area for the fourth, an air force officer said.

No civilian injuries or damage were reported, the officer said on condition of anonymity, citing department policy.

"Air-to-air missiles do not explode unless the pilot turns the fire switch on," he said.

Investigation launched
The two planes had taken off earlier from an air base in Wonju, about 80 miles east of Seoul, he said.

An investigation was under way to determine the cause of the collision, and all F-5E jets were grounded, he said.

South Korea's air force has about 100 F-5E jets that it purchased from Northrop Corp. of the United States between 1974-1978.

One of the jets hit the other from behind before crashing, South Korea's Yonhap News Agency reported. The other jet sustained damage to its tail wing, it said.

Air force officials declined to comment on the report, citing an ongoing investigation.

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